Siemens



ELECTRIC RAIL-WAY SYSTEM.

No. 502,539. Patented Aug. 1 1893.

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GEORG WILHELM VON SIEMENS, OF BERLIN, GERMANY, ASSIGNOR TO SIEMENS &HALSKE, OF SAME PLACE.

ELECTRIC-RAILWAY S'YSTEM.

SPECIFICATION forming part of Letters Patent No. 502,539, dated August1, 1893.

Application filed March 29, 1893. Serial No. 468,177.

and 2,522 and Nos. 570,681 and 2,394,

which I have obtained Letters Patent as follows: in England, No. 10,926,dated August 26, 1886, and in Austria-Hungary,Nos. 31,923 and 2,522 andNos. 570,681 and 2,394, dated August 7, 1886,) of which the following isa specification.

The use of transformers, or secondary generators for transmittingelectrical energy, offers the advantage that a much higher tension maybe employed than is possible with transmission by continuous current, sothat considerable energy canbe transmitted through great distances bymeans of comparatively small conductors, while at the same time theregulation of the power of the motor is capable of being efiected muchmore easily.

For the purposes of this invention, any known construction of alternatecurrent machine is employed for generating the current, while for themotor to be driven by the current, there is employed a dynamo machinethat can produce continuous currents.

In applying this invention to electric railways, in which the motors onthe carriage receive the current from the traffic rails, or fromconductors extending alongside of said rails, the transformers areemployed as follows: Transformers are placed at certain distances apartalong the line of traffic rails, the primary coils receiving the currentfrom the generators, being arranged either in parallel are or in serieswith the conductors therefrom, or each having a separate circuit, whilethe terminals of the secondary coils are connected respectively to thetwo traffic rails, when these are used as the conductors, or to theseparate working conductors, when these are employed- The traffic rails,or the working conductors may be continuous and fed from all of thetransformers, or divided into sections, and each section fed from onetransformer, or on the carriage may be placed a transformer conductors(N0 model.) Patented in Austria-Hungary August 7, 1886, Nos. 31.923

and in England August 26, 1886, No. 10,926.

whose primary coils are connected in the Well known manner, throughsliding or rolling contacts to the conductors which convey the currentsfrom the generator thereto, while the secondary coils convey inducedcurrents to the electro-motor on the carriage. It is preferred toarrange the transformers either in parallel are or on separate circuits,as by such means only can an automatic regulation thereof be obtained.By the automatic or non-automatic regulation of the alternate currentmachine, the tension at the terminals of the primary coils would then bealways constant.

In the accompanying diagrams which illustrate my invention, similarnumerals of reference indicate like parts.

Figure 1 shows a number of transformers coupled in parallel between thefeeder conductors from the generator and the working conductors of thesystem. Fig. 2 shows a number of transformers with their primary coilsin series with the feeder conductor from the generator, and theirsecondary coils connected to separate sections of the workingconductors. Fig. 3 shows the transformers arranged in separate feedingcircuits from the generator. Fig. 4 shows a carriage, on which ismounted a motor, a transformer having its primary coil in parallelthrough movable contacts with the feeder conductors from the gen erator,and a current modifying coil in the primary; and further, shows themotor con-- nected to the secondary coil of the transformer. Fig. 5shows one of my methods of regulating the transformer, and it consistsin means for varying the number of secondary coils in action, accordingto the demands of the load.

In the diagrams, 1O represents'any suitable generator of alternatingcurrent; 11, the feeder from and to V the generator. In Fig. 4, theseconductors serve as the working conductors. p

12 are the working conductors. These conductors may consist of the railsof a tramway, or of one rail and a conductor placed parallel thereto, orthere may be separate, distinct conductors placed above, below, orotherwise disposed relative to the rails upon which the vehicle moves.They may be continuous or divided into sections, as desired.

13 is a transformer of the usual type having primary and secondary coils14 and 15.

In Fig. 1, the transformers are shown coupled in parallel between thefeeder conductors l1 and the working conductors 12: that is to say, theprimary coils of the transformers are connected to the conductors 11,and the secondary coils 15 to the conductors 12.

In Fig. 2, the transformers 13 are arranged in series. All the primarycoils are in series with the conductor 11, while the secondary coils areeach connected by itself to a single section of the working conductors12.

In Fig. 3, the primary coils of the separate transformers are fedthrough separate feeder conductors 11, while the secondary coils areconnected in parallel arc with the continuous conductors 12.

In each of the arrangements shown, the transformers are separated at adistance from each other along the line of the road. This distance willdepend upon the character of the currents transmitted, length of theroad, the.

In Fig. 4, the arrangementis somewhat different;instead of a number oftransformers arranged along the line of the road, a single transformer13 is placed upon the vehicle. In this case, the primary coil 14 of thetransformer is connected to sliding or rolling contacts 16, which bearrespectively, one, for instance, upon one of the feeder conductors 11and the other upon the other of the feeder conductors, or upon a railsuitably connected to one of the feeder conductors. The secondary coil15 has its terminals connected to the motor 17. 18 is a switch forbreakingthe circuit between the secondary of the transformer and themotor. This switch can be arranged in a manner well understood, toreverse the current through the motor. Anysuitable type of motor may beused 1'. 6. one adapted to be worked with alternating currents, whichmay be an alternating motor, or a machine which, when used as adynamo,will generate constant currents; that is to say, a machine of theSiemens or Gramme type, having its field magnets subdivided by makingthem of laminated plates.

In Fig. 5, 11, 11 indicate the main or feeder conductors; 13 is thetransformer in diagram; 12, 12 are the working conductors; 14 is theprimary conductor of the transformer, and 15 is the secondary conductorof the transformer. The coil of the secondary conductor 15 is dividedinto sections which are connected to the contact plates 20. 21 is acontact arm which moves over these contact plates 20. It will be noticedthat in the extreme left hand position of the contact arm 21 only one ofthe secondary coils is in circuit, while in the extreme position to theright hand, all the coils of the secondary are in circuit; and in anintermediate position, an intermediate iron core.

number of coils will be in action, according to the position of saidcontact arm. This is a very simple and efficient method of regulation,and tends to save much energy which would otherwise be wasted.

In the arrangement shown in Figs. 1 and 3, where the secondaries of thetransformers are in parallel with the feeder conductors, all of saidtransformers will be active at the same time, and each one will do workin proportion to the resistance of its secondary circuit. Owing,however, to the motion of the carriage, this resistance will varyaccording to the distance of the carriage from the particulartransformer from which it is receiving current. The difference ofpotential at the terminals of the secondary coils will have to be takencomparatively low, having regard to the difiiculty of effecting aperfect insulation of the traffic rails, or separate conductors whichdistribute current.

The above described system,as all other systems for the transmission ofenergy for a similar purpose-requires that a regulating device be usedto determine the speed of the carriage, &c. For this purpose I make useof the following device:

19, Fig. 4, diagrammatically represents a wire coil or bobbin providedwith a movable For electrical reasons, which are readily understood, ifthe iron core is introduced into the bobbin, a counternelectro-motiveforce to that traversing the primary of the transformer will be induced,and will therefore cut down the current in the primary.

Instead of using this device, various other well known means formodifying the current transmitted to the motor on the vehicle may beemployed.

I do not limit myself to the use of any particular kind of contacts, asany suitable means may be employed for putting the electro-motor ormotors on the vehicles in operative relation with the source of energy.

7 I do not in this application claim broadly the employment of a currentmodifying transformer in an electric railway system of the characterdescribed,as such feature has been made the subject of a companionapplication, Serial No. 468,176, filed March 29, 1893.

Having thus described my invention, I claim 1. In an electric railway, asource of alternating currents, feeder conductors extending therefrom, avehicle, an electro motor adapted to be actuated by alternatingcurrents, and a transformer located on said vehicle having its primarycoil in operative relation to said feeder conductors and its secondarycoil electrically connected to the motor.

2. In an electric railway, a source of alternating currents, feederconductors extending therefrom, a vehicle, an electro motor adapted tobe actuated by alternating currents, a transformer located on saidvehicle having its primary coil connected to said feeder conductors andits secondary coil electrically connected to the motor, and means formodifying the current supplied to the motor.

3. In an electric railway, the combination ofa source of alternatingcurrents, conductors extending therefrom, a number of vehicles movingalong the said line of way, transformers located on said vehicles,motors also located on said vehicles and electrically connected with thesecondary circuits of the transformers, and means for conveying currentfrom the conductors leading from the generator to the primary circuitsof the transformers.

4. In an electric railway, the combination of a source of alternatingcurrents, conductors extending therefrom, a number of vehicles movingalong the said line of way, transformers located on said vehicles,motors also located on said vehicles and electrically connected with thesecondary circuits of the transformers, means for conveying current fromthe conductors leading from the generator to the primary circuits of thetransformers, and means for regulating the supply of energy transmittedthrough the primary coil of the transformer.

5. In an electric railway, a source of alternating currents, conductorsextending therefrom, a moving vehicle orvehicles upon theline ofrailway, transformers located on said vehicles connected to saidconductors, motors also located on said vehicles, means for conveyingcurrent from the generator to the motors, and a counter-electro motiveforce coil also located on the vehicles to regulate the supply of energyto the motor. I

6. In an electric railway, a source of alternating currents, conductorsextending therefrom, a moving vehicle or vehicles upon the line ofrailway, transformers located on said vehicles connected to saidconductors, motors also located on said vehicles, and a counter electromotive force coil connected to the primary coil of the transformer, saidmotive force coil having an adjustable core to regulate the supply ofenergy to the motor.

7. In an electric railway, a source of alternating currents, conductorsextending therefrom, a vehicle or vehicles moving along the line ofrailway, transformers connected to said conductors and located on saidvehicle or vehicles, motors also located on said vehicle or vehicles,and traveling contacts moving along the conductors and carried by thevehicle or vehicles, said contacts being in circuit with the primary ofthe transformer, the secondary circuits of the transformer beingconnected to the motors.

S. In an electric railway, a source of alternating currents, overheadconductors connected to said source and extending along the line ofrailway, a vehicle or vehicles moving along the line of railway,transformers located on said vehicle or vehicles, motors also located onsaid vehicle or vehicles, means for conveying the current from theoverhead conductors to the transformers, and means to regulate thesupply of energy to the motors.

9. In an electric railway, a source of alternating currents, overheadand surface conductors connected to said source and extending along theline of railway, a vehicle or vehicles moving along the line of railway,transformers located on said vehicle or vehicles, motors also located onsaid vehicle or vehicles, means for conveying the current from theoverhead and surface conductors to the transformers, and means toregulate the supply of energy to the motors.

In testimony whereof I affix my signature in the presence of twowitnesses.

GEORG WILIIELM VON SIEMENS.

Witnesses:

GUSTAV STENZEL,

MAX WAGNER.

